Complexation and physicochemical analysis of hydrophobic molecules of methyl jasmonate with Hydroxypropyl-β–Cyclodextrin

In the present study, methyl jasmonate (MeJa) was included in 2-hydroxypropyl-beta-cyclodextrin (HP beta CD) by grinding (M-1), freeze drying (M-2), co-precipitation + freeze drying (M-3) and by applying supercritical carbon dioxide (M-4). FT-IR/ATR, FT-Raman, TGA, and DSC analyses of the complexation products confirmed that MeJa/HP beta CD complexes were formed by the four different examined methods of inclusion. FT-IR/ATR supported the inclusion, mainly based on the reduction of intensity of absorption at the wavelength of maximum absorbance of free MeJa (1733 cm(-1)), which was 27.69 au before inclusion. From these results, M-3 (2.29 au) and M-4 (0.90 au) were the most efficient techniques for complexation. TGA, and DSC analyses pointed out that the complexes formed by the methods M-3 and M-4 had the least loss of mass below approximately 305 degrees C (the temperature that free HP beta CD starts to decompose thermally). Except for M-1, the results of antioxidant activity (AA) based on the DPPH assay revealed that the AA of the inclusion compounds were higher than that of free MeJa (alpha = 0.05). The best methods in terms of AA and thermal stability of the formed inclusion compounds were M-3 and M-4.